Realizing what the moving stars of the Mermaid's Tail constellation meant, Teredor explains that the Dark Sirens emerge from the deepest depths of Andros' oceans every time the stars within the constellation shine brightest in the sky. Using any bodies of water to reach the mainland, the four Sirens, Nazca, Terala, Unla and Limes, sneak into Niobe's bedroom through the fountain in the back and attack her. As they drag her back into the depths with them, their leader, Limes, leaves behind a coral necklace at the scene of the crime to signal their presence to any who would come across the ransacked room. With Niobe as their target, the Winx come to realize that they plan to convert her into becoming their fifth and final Siren, and Teredor reveals that the Sirens will gain invincibility if that were to happen. So, the Winx rush into the oceans of Andros in their Harmonix to rescue her before it is too late.

Nazca watching as Limes demands for Niobe to forget her name.

Nazca makes her physical debut in the Deep Blue, the home of her and her Siren sisters. Unaware of the Winx and Selkies spying on them, Nazca simply watches on as Limes demands Niobe to forget her name and relinquish herself to the darkness of the Deep Blue. Naturally, Niobe refuses her demands but Limes mocks her for thinking she had any choice in the matter. She then goes on to explain the process in which Niobe will be converted into Asfodelia until Aisha leaps from her hiding spot and attacks the Sirens with her Mystic Veil spell. The spell only hits Unla as Nazca and the rest of the Sirens find themselves met with six battle-ready fairies in their home. Nazca and Limes quickly beat Aisha away from Niobe and all of them begin to engage in a heated battle with the Winx to make sure Niobe does not get taken away. Unfortunately, the battle requires so much of their attention that they are completely unaware that the Selkies have taken Niobe up to the surface.

Nazca preparing to launch a Convergence with her sisters.

Eventually, the battle reaches a point where Limes is able to will the darkness of the Deep Blue into spreading and intensifying to help her and her sisters hide and gain strength. Once it has spread and intensified enough, Nazca joins her sisters in a Convergence and unleashes it upon the Winx. Their Convergence proves to be so powerful that Tecna and Musa find themselves unable to hold it back for much longer, however, the Sirens' formation is quickly broken once Flora invokes the will of the surrounding algae into glowing so brightly that it disorients them. Nazca and her sisters are then hit by Aisha's Thirteenth Seal and struggle to hold it back. When Limes demands to know the identity of the fairy responsible for this, Aisha proclaims herself to be the Princess of Andros who the Sirens made a grave mistake in challenging. Nazca and her Siren sisters are then thrusted into the deepest depths of the Deep Blue by Aisha's Thirteenth Seal and are banished for good.

Magical Abilities

Nazca blasting Aisha down.

As a creature of darkness, Nazca and her Siren sisters all utilize dark magic and, as stated by Teredor, have the ability to traverse any and all bodies of water to get from place to place. Also, like all magical creatures, Nazca can create generic shields and magical blasts.

Nazca has only been seen demonstrating her ability to shoot blasts of dark magic at her opponents.

Trivia

Though Limes is stated to be the youngest of the Sirens as the last ancient queen to be converted into one, it is unknown how old Nazca is compared to her Siren sisters.

Nazca is the only one of the Sirens to not demonstrate a power specific to her.